Well pipe sealing device



May 31, 1966 c. c. BROWN 3,253,835

WELL PIPE SEALING DEVICE Original Filed Nov. 23, 1959 5 Sheets-Sheet 1 wvsw r'a BY %/Z 6 ATTORN S 31, 1966 c. c. BROWN WELL PIPE SEALING DEVICE Original Filed Nov. 23, 1959 5 Sheets-Sheet 2 May 31, 1966 c. 0. BROWN WELL PIPE SEALING DEVICE Original Filed Nov. 23, 1959 5 Sheets-Sheet 3 mww BY ZQA 1; QTTukMEy United States Patent 3,253,835 WELL PIPE SEALING DEVICE Cicero C. Brown, Houston, Tex, assignor to Brown Oil Tools, Inc., Houston, Tex., a corporation of Texas Original application Nov. 23, 1959, Ser. No. 854,870, now

Patent No. 3,154,145, dated Get. 27, 1964. Divided and this application Feb. 3, 1964, Ser. No. 341,878

7 Claims. (Cl. 277-35) This invention relates to a sealing device for sealing around multiple pipe strings while such multiple pipe strings are being run into a well bore. This application is a division of my prior co-pending application, Serial 'No. 854,870, filed November 23, 1959, now Patent No. 3,154,145, issued October 27, 1964.

It has become the general practice to simultaneously produce well fluids from a plurality of producing zones which are traversed by a single well bore. The production from each zone must be conducted to the surface through an independent pipe or tubing string and therefore the producing zones must be separated or sealed off from each other by Well packers. The running in and placement of the well packers and of the multiple tubing strings is accomplished at a time when the various producing zones are fully prepared for production. With the producing zones ready for production during the running in of well packers and multiple tubing strings it is desirable to provide a device for sealing around each of the tubing strings as they are lowered in the well bore and such device should be readily removale to allow quick completion and installation of the fixed tubing head when the packers and tubing strings are in their final position.

The running of such multiple tubing strings into a well bore may be done individually with the first string and its packer being run completely into position and then the second string and its packer being run into the well bore and individually landed in the well packer of the previous string as disclosed in my prior Patent No. 2,903,066. However, the difiiculty sometimes encountered in landing a string in the well packer within the bore has caused operators to simultaneously run multiple tubing strings and packers into the well. It is therefore one object of this invention to provide a sealing device for sealing off around a plurality of pipe strings, whereby the well is maintained under control while the multiple strings are being lowered into position within the well.

An important object is to provide a sealing device for sealing around a plurality of pipe strings during the lowering of the pipe strings into the well which will maintain the well under control and be readily removable for the completion of the well.

Another object is to provide a sealing device of the character described providing sealing against each of the multiple pipe strings and sealing against the interior of the well bore in which the device is installed.

A further object is to provide a resilient sealing device for sealing around multiple pipe strings having means preventing the extrusion or reversal of the resilient sealing members when exposed to pressure in the well bore.

The construction designed to carry out the invention will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

FIGURE 1 is a schematic View. illustrating the device of the present invention installed in a multiple pipe string installation in which the packers and pipe strings are being Patented May 31, 1966 run into a well bore which is traversed by a plurality of producing zones;

FIGURE 2 is a transverse sectional view of the sealing unit of the present invention which is employed to seal around the multiple strings during running in of the strings, said view illustrating the inner element of said unit being lowered into position;

FIGURE 3 is a plan view of the sealing element with the inner element in place;

FIGURE 4 is a transverse sectional view taken on lines 44 of FIGURE 3 illustrating the details of construction of the sealing unit of the present invention.

FIGURE 5 is a partial transverse section taken on lines 55 of FIGURE 4 illustrating the details of construction of the sealing unit of the present invention;

FIGURE 6 is an exploded perspective view illustrating the relationship between the dog holder and dogs.

In the drawings the numeral 10 designates a well bore which traverses a plurality of well producing formations or zones, F1, F2, F3 and F4. A well casing 11 extends throughout the length of the well bore in the usual manner and has perforations 11a, 11b, 11c and 11d opposite the formations F1 through F4, respectively, whereby fluid from the formations or zones may flow into the casing. A tubing head 12 having the usual supporting seat 13 is mounted at the upper end of the casing 11 above the ground level but below the derrick floor 14; the usual rotary table 15 is located above the derrick floor.

In setting up multiple production from the well bore 10, it is necessary to dispose of all packers within the well casing to separate the various producing zones and to lower multiple tubing strings so that well fluids from each zone may be separately produced. For the purpose of handling the multiple strings of pipe, an elevator device, generally indicated at A and which is generally known in the art, is provided. In addition, a spider device, generally indicated at B, is employed. The elevator device A and the spider B may be of any suitable type normally used for the lowering of multiple strings and well packers simultaneously.

In FIGURE 1, the elevator device A is provided with four openings A1, A2, A3 and A4 with each opening adapted to receive pipe supporting gripping or slip elements. The elevator device A is, of course, adapted to be supported by the usual cable or line 16 which depends from the traveling block (not shown) of the drilling rig while the spider device B is arranged to be mounted on theupper end of the rotary table 15. The spider device B is also provided with four openings B1, B2, B3 and B4 through which the multiple strings extend and which are adapted to receive pipe supporting slips.

Referring to FIGURE 1, the Well packers P1, P2, P3 and P4 are shown to be within the well casing 11 with the uppermost packer P4 being just below the supporting seat 13 on tubing head 12. With the packers in this position the sealing device C has been installed above the tubing head 12 as hereinafter more clearly explained.

Because the major length of the pipe strings T1 through T4 are normally located above the uppermost packer, there is a period of time while the four pipe strings are being lowered that the well will be open. Therefore, it is desirable after the four packers have been moved into the casing that a sealing off around the pipes be effected. For this purpose the sealing unit C is mounted on the upper end of the tubing head 12. This sealing unit has a plurality of sealing elements C1, C2, C3 and C4 which engage around the tubing strings T1 through T4, respectively. When in position, a sealing around all pipe strings is effected and as additional stands of tubing are connected in the strings, the sealing unit C functions tomaintain the upper end of the casing closed. It might be noted that the additional stands of tubing are connected to the respective strings by handling all four strings simultaneously with the elevator device A and the spider device B.. As is 1 will then be connected to the four trings T1 through T4,

after which the elevator device is re-connected with the upper ends of the string and the pipe supporting means landed in the tubing head body. Thereafter suitable installation of outlet lines and control valves will be made for the completion of the well.

Normally the multiple well packers are located at a considerable distance below the surface of the well and, therefore, after the last or uppermost packer has been 'started into the well bore, there is a considerable length of pipe still to be lowered into the well; as a matter of fact, this length of pipe usually constitutes the major portion thereof. This distance may vary from 2,000 or 3,000 to as much as 8,000 feet. Since the packers are lowered into the bore in non-sealing position, it is evident that the well is substantially open during the lowering of the strings into the bore. It has been found desirable to provide a sealing unit for sealing off around the multiple strings during the lowering of the strings into the well after the uppermost packer has already been positioned in the well and the sealing unit of the present invention will efiectively seal off the well bore and around the multiple strings as more clearly illustrated in FIGURES 2, 3 and 4.

The sealing unit of the present invention includes an annular body or housing 17 having a base flange 18 which is adapted to be secured to the upper end of the tubing head 12 by suitable bolts 19. The body or housing includes an axial bore 20 which may be beveled inwardly at its lower end. An enlarged counterbore 21 at the upper end of the body permits the provision of an annular inclined seat 22 within the bore of the body. A locking collar 23 is adapted to be threaded, preferably by acme threads 24, onto the upper end of the body and this collar projects inwardly therefrom. The collar has an inwardly directed flange 25 on the upper portion and the under side of the flange forms an internal annular shoulder 26 within said collar. A plurality of vertical slots or recesses 27, which are spaced at circumferential points around the collar, are formed in the inner periphery of the flange 25.

A sealing assembly generally indicated at D is adapted to mount within the housing or body 17. The sealing assembly includes an upper block 28 which is generally circular in shape and a complementary lower block 29; the blocks are secured together by suitable bolts 30 as shown in FIGURE 2. The block 28 has radially extending lugs 31 which are of a shape to engage and move through the recesses 27 provided in the collar 23. An eye 32 extends upwardly from the block 28 whereby a cable or line 33 may be employed to lower the sealing assembly D into position. Resilient sealing element 34 including an outer depending lip 34a and a plurality of sealing sleeves 3412, one of these sleeves being provided for each pipe string, is positioned on the underside of block 29 as hereinafter more fully described. As shown in FIG- URE 4, the sealing sleeves each have a bore 35 which is adapted to snugly engage the pipe string (shown in dotted lines) which extends therethroug-h. The outer surface of each sealing sleeve is tapered or reduced as indicated at 36 whereby the sleeve is in engagement with the pipe, any pressure exteriorly of the sleeve will urge the same into tighter sealing engagement with the pipe.

The details of construction of sealing sleeves 34b are clearly shown in FIGURES 4 and 5. Cylindrical dog holders 37 are secured within the bores 38 and 39 which extend through upper block 28 and lower block 29 respectively, and are suitably secured therein as by welding with upwardly facing shoulders 40 on holders 37 engaging shoulders 41 which are formed by the bores 39 through lower block 29 being larger than the bores 38 through upper block 23. The lower portion of dog holders 37 are provided with T-slots 42 in which T- hangers 43 of dogs 44 are supported. T-slots 42 should be sufficiently larger than T-hangers 43 to allow movement of dogs 44 as hereinafter more fully described. Stop rings 45 are positioned as shown to limit the inward movement of T-hangers 43.

With blocks 28 and 29 assembled with dog holders 37 positioned in bores 38 and 39 and with dogs 4-4 and stop ring 45 properly positioned resilient sealing element 34 is integrally formed or bonded to such components. As mentioned, sealing element 34 is formed to provide depending lip 34a which will engage bore 20 of housing 17 and to provide sealing sleeves 34b surrounding and depending from each set of dogs 44.

When tubing is being run downwardly through sealing device (3, the innermost surface of dogs 44 will slide on the exterior of the tubing and sealing sleeves 34b will seal against the exterior of the tubing. When any pressure occurs within the well bore 10 below housing 17 then such pressure will act on sealing sleeves 34b and they will be forced into sealing engagement with the tubing and dogs 44 will provide sufficient backing to prevent sleeves 3% from being reversed or extruded into the space between the tubing and the interior of'dog holders 37. Also, such pressure will be exerted against lip 34a to force it into sealing engagement with bore 20 of housing 17 whereby sealing unit C will contain the well pressure within the well bore :10.

The available movement of dogs 44 must be sufficient to allow tubing collars to be run through the device and to allow the dogs to engage the exterior of the tubing when pressure occurs in the well bore 10. Also, sealing sleeves 34b must have sufficient resilience to allow the passage of tubing collars and to return to sealing engagement with the exterior of tubing when pressure occurs within the well bore.

If desired, the connection between dogs 44 and dog holder 37 may be in the form of a tongue on the dogs which engages in a groove in the lower exterior of dog holder 37 with the groove being larger than the tongue to allow sufiicient pivotal movement of the dogs to allow the passage of collars and to engage the exterior of tubing. Such configuration is not shown in the drawings.

In using the sealing unit, the body or housing 17 is mounted on the tubing head 12 and after the uppermost packer is in position within the well, the multiple strings are extending upwardly therefrom and supported by the spider device B. At this time the sealing assembly D is engaged over the upper ends of the pipe strings and each pipe string is passed through one of the sealing sleeves 34. The pipe strings will then be supported by the elevator device A and the spider device B will be removed; then by means of the line 33 the sealing assembly D is lowered downwardly, sliding along the pipes until it moves into position within the body or housing 17. As'the sealing assembly enters the housing, the radially extending lugs 31 move downwardly through the recesses 27 in the collar 23; by the time the beveled surface 29a of the bloclk'29 engages seat 22, the lugs 31 have moved below the level of the annular shoulder 26 formed within the collar. Thereafter, the looking collar 23 is rotated to move the recesses 27 out of alignment with the lugs 31 of the assembly (as indicated in dotted lines in FIGURE 3), after which the fast-acting relatively coarse threads 24 function as a cam to force the assembly D into tight sealing position on the seat '22. Thus,'the sealing assembly is locked against upwarddisplacement within the body 17. The sealing sleeves 34b are in engagement with the exterior surfaces of the pipe strings and seal off therearound and with the sealing assembly in place, the upper end of the well bore is closed as shown in FIGURE 1, whereby the pipe string may subsequently be lowered into the well Without danger of the well getting out of control during the running-in operation.

As previously explained, after all lengths of the pipe strings have been run, the sealing assembly D is removed by merely first rotating the locking collar 28 to realign the lugs 31 with the recesses 27 and then pulling the assembly upwardly over the upper ends of the pipe strings. Thereafter, a suitable supporting block (not shown) which supports all pipe strings from the tubing head is placed in position and the final well hook-up is completed.

Thus, from the foregoing it can be seen that the present invention provides a device which will seal around multiple pipe strings while such pipe strings are being run into the well and will maintain the well under control during the period of running the pipe strings. The device provides a pressure seal surrounding each of the pipe strings individually and around the bore which seal is resilient but prevented from extruding o-r reversing whereby the well pressure in the well bore will be controlled. The device also provides a simple locking mechanism for retaining the sealing member in position.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details or the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

l. A sealing assembly for sealing around a plurality of well pipes and adapted to be supported in an outer body, said assembly including,

a supporting block for seating within the body and having -a plurality of vertical openings therethrough,

a resilient sealing element secured to the lower surface of said block and having openings in registration with the openings in the block,

a plurality of resilient sealing sleeves extending downwardly from the sealing element, each sealing sleeve having its bore aligned with the registered openings in the block and sealing element and of a diameter to seal with a well pipe extending therethrough,

and movable non-resilient means disposed with the upper portion of each sealing sleeve to back up said sleeve when the sleeve is sealing about the pipe extending therethrough, said non-resilient means having limited outward radial movement to permit limited outward deformation of said sleeve whereby enlargements on the well pipe may pass through said sleeve.

2. A sealing assembly for sealing around a plurality of well pipes and adapted to be supported in an outer body, said assembly including,

a supporting block for seating within the body and having a plurality of vertical openings therethrough,

a resilient sealing element secured to the lower surface of said block and having openings in registration with the openings in the block,

a plurality of resilient sealing sleeves extending downwardly from the sealing element, each sealing sleeve having-its bore aligned with the registered openings in the block and sealing element and of a diameter to seal with a well pipe extending therethrough,

a set of back-up members disposed within the upper portion of the bore of each sealing sleeve whereby the lower portion of each sleeve may engage and seal with a pipe extending therethrough,

and means mounting each set of back-up members upon the supporting block for radially outward movement whereby enlargements on the well pipe may pass therethrough.

3. A sealing assembly as set forth in claim 2, together i with a downwardly facing annular sealing lip on the periphery of the resilient sealing element, which lip is exposed to the pressure below said element when the same is in position within the body.

4. A sealing assembly as set forth in claim 2, wherein the means mounting each set of back-up members comprises,

a collar secured within each opening in the supporting block,

and coacting means on the lower portion of the collar and on each back-up member for suspending said member therefrom whereby at least the lower portion of each back-up member may undergo limited radial movement.

5. A sealing assembly as set forth in claim 2, wherein the resilient sealing member is integral with the sealing sleeves and is formed of the same resilient material and also wherein,

the sealing member is molded to the underside of the block and each sealing sleeve is molded to its respective set of back-up members.

6. A sealing assembly for sealing around a plurality of well pipes and adapted to be supported in an outer body, said assembly including,

a supporting block for seating within the body and having :a plurality of vertical openings therethrough,

a resilient sealing element secured to.the lower surface of said block and having openings in registration with the openings in the block,

a plurality of resilient sleeves, one for each opening in said sealing element and extending downwardly from said sealing element,

each sealing sleeve depending from and having its upper end supported by said resilient sealing element and having its bore aligned with the registered openings in the block and sealing element and of a diameter to seal with a well pipe extending therethrough, and

the outer surface of each sealing sleeve being exposed to the pressure in the area surrounding the pipe ex tending therethrough and below the assembly whereby said pressure acts to urge said sleeve into tight sealing engagement with the pipe extending therethrough.

7. A sealing assembly as set forth in claim 6, together with a downwardly facing annular lip on the periphery of the resilient sealing element, which lip is exposed to the pressure below said element when the same is in position in the body.

References Cited by the Examiner LAVERNE D. GEIGER, Primary Examiner.

SAMUEL B. ROTI-IBERG, LEWIS J. LENNY,

Examiners.

L. RANEY, J. MEDNICK, Assistant Examiners. 

1. A SEALING ASSEMBLY FOR SEALING AROUND A PLURALITY OF WELL PIPES AND ADAPTED TO BE SUPPORTED IN AN OUTER BODY, SAID ASSEMBLY INCLUDING, A SUPPORTING BLOCK SEATING WITHIN THE BODY AND HAVING A PLURALITY OF VERTICAL OPENINGS THERETHROUGH, A RESILIENT SEALING ELEMENT SECURED TO THE LOWER SURFACE OF SAID BLOCK AND HAVING OPENINGS IN REGISTRATION WITH THE OPENINGS IN THE BLOCK, A PLURALITY OF RESILIENT SEALING SLEEVES EXTENDING DOWNWARDLY FROM THE SEALING ELEMENT, EACH SEALING SLEEVE HAVING ITS BORE ALIGNED WITH THE REGISTERED OPENINGS IN THE BLOCK AND SEALING ELEMENT AND OF A DIAMETER TO SEAL WITH A WELL PIPE EXTENDING THERETHROUGH, AND MOVABLE NON-RESILIENT MEANS DISPOSED WITH THE UPPER PORTION OF EACH SEALING SLEEVE TO BACK UP SAID SLEEVE WHEN THE SLEEVE IS SEALING ABOUT THE PIPE EXTENDING THERETHROUGH, SAID NON-RESILIENT MEANS HAVING LIMITED OUTWARD RADIAL MOVEMENT TO PERMIT LIMITED OUTWARD DEFORMATION OF SAID SLEEVE WHEREBY ENLARGEMENTS ON THE WELL PIPE MAY PASS THROUGH SAID SLEEVE. 